<!DOCTYPE html>
<html lang="zh-CN">
	<head>
		<meta charset="UTF-8" />
		<meta name="viewport" content="width=device-width, initial-scale=1.0" />
		<title>002-box-sizing</title>
		<style>
			.box1 {
				width: 200px;
				height: 200px;
				background-color: skyblue;
				padding: 5px;
				border: 5px solid black;
			}

			.box2 {
				width: 200px;
				height: 200px;
				background-color: skyblue;
				padding: 5px;
				border: 5px solid black;
				box-sizing: border-box;
			}
		</style>
	</head>
	<body>
		<div class="box1"></div>
		<hr />
		<div class="box2"></div>
	</body>
</html>
